Automatically-adjustable hydraulic pump.



P. H. MISTRAL & A. R. BROCHE. AUTOMATIUALL'Y ADJUSTABLE HYDRAULIC PUMP.

APPLICATION FILED MAR.11, 1913.

Patented Dec. 1

m. v. m 0.1. L m

Witnesses:

UNTTED STATES PATENT oEErcE.

PAUL 'HENRI MISTRAL AND ALFRED RAOUL BROCHE, 0F NEUILLY-SURJ-SEINE,

FRANCE.

AUTOMATICALLY-ADJUSTABLE HYDRAULIC PUMP.

Application led March 11, 1913.

To all whom it may concern Be it known that we, PAUL HENRI Mrs- TEAL and ALFRED RAOUL BROCHE, both of 73 Boulevard Victor Hugo, Neuilly-sur- Seine, Seine, Republic of France, mechanics, have invented an Automatically-Adjustable Hydraulic Pump, of which the following is a full, clear, and exact description.

The invention has for its object a hydraulic pump characterized by the fact that its outflow is automatically adjusted by a special device employingv the pressure of delivery for automatically increasing or diminishing the length of the piston stroke and, consequently, the outow of "the pump.

The invention is illustrated by way of eX.- ample in the accompanying drawing, in

which Figure 1 is a side view of the pump, the

piston being at the bottom of its stroke; Fig. 2 is a vertical section made according to line A-A of Fig. l, the piston being at the top of its stroke.

As illustrated in the drawing, the pump forming the subject-matter of the present invention comprises a pump barrel a with which communicates a suction pipe b leading to the feed tank and a delivery pipe or chamber c connected by a pipe d to a tank or receiving apparatus. Check valves b and e', suitably arranged, allow the suction and the delivery Aof the liquid.

In the pump barrel a can move a piston e on the rod e" of which is secured a platef serving as a bearing fora coil spring g arranged between said plate and the pump barrel.

The part of the piston. rod e placed above the plate f is provided with a screw thread z adapted to engage in a nut z' of Ispecial arrangement. This nut is internally provided with a female screw thread z" receiving the screw thread of the piston rod e and is provided xteriorly with a screw thread i? of contrary direction relatively to the screw thread z". This screw thread allows of the nut i being mounted in a cap j upon which can act a cam k keyed on a shaft k. This cap j is provided with a vertical groove l in which is fitted a member Z integral with the plate f and adapted to prevent said cap from rotating when the nut is rotated, as will be seen hereafter.

The nut z' constitutes atits base a pulley m with two grooves m and m2, the former Specification of Letters Patent. v

Patented lDec.I 1, 1914.

seria1 No. 753,527..

receiving a cable n engaged in a flexible tube n and adapted to connect the pulley and, consequently, the nut z to an automatic outflow regulator. Said regulator comprises a hollow cylinder 0 arranged at right angles to the tube c and communicating with the latter. In the cylinder o can move a smooth piston y?, having agreater length than said cylinder, the free end of which can slide in a nut engaged in a plate 1- provided with a screw threaded opening. Said plate 1- is' held by two` arms s integral with the cylinder o (Fig.

On the piston p is secured a disk t serving y as a bearing for one of the ends of a coil The regulator'being adjusted by means ofthe nut g which compresses the spring u for obtaining the desired tension, the actuating cam is set in motion;- The piston e will be driven within the barrel a under the action of said cam and will drive back the liquid4 into the chamber 0. `As the cam ,moves upward, the spring g, which had been compressed, expands and raises the piston e, thus producing the suction of the liquid in the pump barrel a and so on. When the pres` sure in the delivery chamber c, exceeds the pressure balanced by the tension of the spring u of the regulator, the piston. p will v be pushed back toward the exterior and will move the disk t kwith it. ,As the latter: is connected by the cable n to the pulley m constituting the base of the. nut z', said'cable by stretching out will impart to said nut a' rotary motion whichwill have for effect to screw this nut into the cap j and to move the latter toward thel rod e of the piston, the length of the stroke of which will thus be diminished. In consequence, the outiow of the pump diminishes automatically and proportionally to the reduction4 of the stroke of the piston and the work, in consequence of this reduction of outflow, diminishes also, so that the force absorbed by the operation of the pump will be constant.

the piston p is pushed back by the spring u of the regulator, the cable n slackens and-the spring m, whichl had been compressed by the rotary motion of the nut z', acts, through the `medium of the cable fe), upon thisnut and causes it to rotate inthe reverse direction, this having for eect tocause the cap j to move upwardly and to increase the stroke of the piston and, consequently, the outflow of the pump. v

It is Vto be understood that the movement 4of the regulating piston p can be transmitted to the nut i in any suitable manner.

The above arrangements are given only by way of example, the forms, sizes and detail devices may be varied according to circumstances without modifying the principle of the invention.

Claims: 4

l. A hydraulic pump comprising a pump barrel, a suction pipe and a delivery pipe connected to said pump barrel, check valves arranged in said pipes, a piston moving in the pump barrel, a plate secured on the piston rod, a spring arranged between said plate and the pump barrel, a screwthread on the piston rod, a nut fitted on this screw thread, a screw thread of contrary direction formed on the outer wallof the nut, a cap fitted on said screw thread, a cam acting upon said cap, a member for preventing the cap from rotating, and devices for causing the nut to rotate whenthe pressure in the delivery pipe exceeds a given value.

- 2. A hydraulic pump comprising a pump barrel, a suction pipe and a delivery pipe connected to said pump barrel, check valves arranged in said pipes, a piston moving in the pump barrel, a plate secured on the piston rod, a spring arranged between said plate and the pump barrel, a screw thread on the piston rod, a nut litted on this screw thread, a screw thread of contrary direction formed on the outer wall of the nut, a cap fitted on'said screw thread, a cam acting upon said cap, a member for preventing the cap from rotating, a pulley with two grooves placed at the base of the nut, a flexible cable engaged in one of the grooves of the pulley, and devices for exerting a traction on this cable when the pressure in the delivery pipe exceeds a given value. f Y

3; A hydraulicpump comprising a pump barrel, a piston moving in the latter, a suction pipeand a delivery pipe connected to the pump barrel, a hollow cylinder secured on the delivery pipe, a piston moving in said cylinder, a disk secured on said piston, a flexible cable secured on said disk, a nut connected by said cable to said disk and receiving the pump piston rod and a cap upon whichacts a cam for actuating saidl pump piston.

4. A hydraulic pump comprising a pump barrel, a piston moving in the latter, a suction pipe and a delivery pipe connected to the pump barrel, a hollow cylinder secured on the delivery pipe, a piston moving in said cylinder, a disk secured on said piston, a nut through which passes said piston, a screw threaded plate holding the nut, two arms `supporting said plate, a tension spring arranged between the nut and the disk, a flexible :lc/able secured on said disk, a nut connected by said cable to said disk and receiving the pump piston rod, and a cap'upon which acts a cam for actuating said. pump piston.

5, A hydraulic pump comprising a pump barrel, a piston moving in the latter, a suction pipe and a delivery pipe lconnected to the pump barrel, a hollow cylinder secured on the delivery pipe, a iston moving in said cylinder, a disk secure on said piston, a nut through which passes said piston, a screw threaded plate holding the nut, two arms supporting said plate, av tension sprin arranged between the nut and the disk, a exible cable secured on 'said disk, a nut connected by said cable -to sa'idfdisk and receiving the pump piston rod, and a oa which acts a cam for, actuating sai pump piston.

The fore oing specification of our automatically a justable hydraulicpump signed by us this 18th day of February 1913.

PAUL HENRI MISTRAL. ALFRED RAOUL BROCHE. Witnesses: HANsoN C. Com?, REN Trmuor.

upon' 

